Multiple-drill-press-controlling means



M. BALCKER.

MULTIPLE DRILL PRESS CONTROLLING MEANS. APPLlcArloN mio 0m18.191s.

Patented Dec. 27, 1921.

4 SHEETS-SHEET l.

raz/vendor M. BALCKER.

MULTIPLE DRILL PRESS CONTROLLING MEANS. APPLICATION FILED Dic. la, Isls.

1,401 388. Patented Dec. 27, 1921.

4 SHEETS-SHEET 2.

M. BALCKER.

MULTIPLE DRILL PRESS CONTRULLING MEANS.

APPLICATION HLED DEC. 18. 1919.

Patented Dec. 27, 1921.

4 SHEETS-SHEET 3.

M. BALCKER. MULTIPLE DHlll PRESS CONTROLUNG MEANS. APPLICATION HLED 050.111.1919.

Patented Dec. 27, 1921.

MARTIN BALCKER, 0F CHICAGO,

ILLINOIS, ASSIGNOR T0 MARQUETTE TOOL & MFG.

CO., A CORPORATION OF ILLINOIS.

HULTIPLEDRILLPRESSCONTBOLLING MEANS.

Specieation of Letters Patent.

Application led December 18, 1919. Serial No. 845,823.

To all lwhom it may concern.'

Be it known that I, MARTIN BALCKER, a citizen of the United States, residing at Chicago, in thecaunty of Cook and btate of Illmois, have" invented certain new and useful Improvements in- Multiple-Drilllress-Controlling Means, of which the following is a specification.

, This invention relates to improvements in multiple drill press controlling means of the pneumatic type, and one of the objects of the invention is to provide an improved device of this character which may be readlly applied to a multiple drill press, and, by Vmeans of which the drill head may be raised and lowered and the mechanical feedin mechanism of the press may be automatica ly` thrown into operation at the proper points in the travel of the drill head.

A further object is to provide an improved device of this character by means of which the" drill head will be arrested vin its movement toward the work to permit the adjustment or positioning of the drills with respect to the jig.

To the attainment of these ends and the accomplishment of other new and useful objects as will appear, the invention consists in the features of novelty in substantially `the construction, combination and arrangement of the several parts hereinafter more fully described and claimed and shown in the accompanying drawings illustrating this invention, and in which:

Figure A1 is a side elevation of an apparatus of this'character showing the same a J- plied to a drill press, portions of the drill y,press being diagrammatically represented in elevation.

Fig. 2 is an enlarged detail view ofthe cylinder and valve controlling means as taken from the left hand side of F ig. 1.

Fig. 3 is a top plan view of the parts shown in F ig. 2. I

Fig. 4 is an'enlarged detail elevation of the tripping mechanism showingr the parts in two different positions.

Fig. 5 is a detail elevation as taken on line 5-5, Fig. 6.

Fig. 6 is a top plan shown in Fig. 5.

Fig. 7 is a detail sectional view of the cylinder and piston.

eferring more particularly to the drawines the numeral l0 designates generally' a view of the parts portion of a drill press frame having a drill head 11 mounted for reciprocation thereon and a controlling element 12 by means of which the mechaical feed`n mechanism of the drill head is controllei The drill head 11 is counterbalanced in the Ordinar and usual manner, and all of the parts a ove referred to are of the ordinary Aand well known type.

The controlling mechanism consists primarily of a cylinder 13 of any desired size and configuration but is preferably provided with a bottom 14 having a port 15 leading from the cylinder to the outside thereo and a head 16 also provided with a port 17 communicating with the interior of the cylinder at the end thereof. The head 16 is provided with a recessed portion 18 having an opening 19 therethrough and in which recess and opening is arranged a gasket or packing 20, the latter surrounding the piston rod 21 and is ada ted to be clamped a ainst the piston ro by means of a suitale nut or bushing 22 provided with external screw threads adapted to engage the threads 23 on the wall of the recess 1n the head 18. Reciprocating within the cylinder 13 and connected to the piston rod 21 is a piston 24 of any suitable construction, b'ut is preferably provided with a body portion 25 of a diameter considerably smaller than the diameter of the cylinder and projecting from the peri hery of the portion 25 intermediate the en sof the body 24 is a circumferential flange 26 which is of a diameter slightly smaller than the internal diameter of the `cylinder so that the periphery of the flange or portion 26 will stand adjacent the cylinder wall. Substantially U-shaped annular flexible packing Patented Dec. 27, 1921'.

aoV

of the flange 26 to encompass t e body'portion 25 of the piston. The open sides of these elements 27 are arranged adjacent the respective ends of the body portion of the piston and one wall of each of the annular members 27 stands adjacent the cylinder walll These elements 27 may be held against displacement in any suitable manner but preferably by means shoulders 28 on the ends of the piston body 25 which overhang the adjacent wall of the respective elements 27. With this construction it will be manifest that as the piston is reciprocated in one direction or the other,

`latter communication the action of the fluid within the cylinder will force the wall of the element 27 against the cylinder wal v j Fluid is supplied to the cylinder 13 from any suitable 'source through a pipe-29 having branches 30-31 leading respectively to the ports 17-15. Arranged within the branch 30 is a three-way valve 32 of the ordinary and well known construction, and which valve is ada ted when in predetermined positions to orm communication between the pipe 29 and the top of the cylinder and when in another position is adapted to cut o the connection between the pipe 29 and the top of the cylinder and establish communication between the top of the cylinder through the valve 32 and outlet opening 33 discharging into the open air.

A similar valve 34 is arranged in the connection 31 between the pipe 29'l and the ort 15 at the other end of the cylinder. his valve 34 is of the three-way type and when in one position establishes communication between the pipe 29, through the connection 31 to the end of the cylinder and when the valve is in another position will cut off this and will establish communication between the end of the cylinder through the port 15 and to the open air through an opening 35 in the valve case.

Links 36-37 are respectively connected with the valves 32-34 and another link 38 is pivotally connected by its respective ends to the links 36-37 so that when-the link 38 is actuated in one direction orv the other the links 36-37 will be correspondingly actuated and the valves will be shifted thereby.

- pre supporting p brackets 48 secured Vas at 54 upon a An operating arm 39 is provided for actuating the valves. This arm 39 is pivotally supported intermediate its ends as at upon a suitable support 41. One end of the arm 39 terminates adjacent the link 38 and is provided with a slot 42 adapted to receive a pin or fastening de'vice43 `so as to form a loose connection between the arm 39 and the link 38. Connected with the other end of the arm 39 by means of a pivot 44 is a bar or rod 45.

The parts thus specifically described are sup orted in any desired or suitable manner erably above the frame 1() of the press and such sup orting means may embody a atform 46 held in position by means of suitable uprights 47, which latter are in turn supported by means of suitable to the drill press frame.

The rod 45 passes through suitable guides 49 and terminates at any desired oint adjacent the base 50 of the frame. onnected at the lower end of the element 45 is a link 51 the free end of which is pivotally connected as at 52 to a rocking support 53, which latter is pivotally suppored intermediate its ends suitable fixed support.

65 dog 55 is pivotally supported intermediate its end preferably by the pivot 54, the end 56 of the dog projecting above the element 53 and is provided with a shoulder 57 which is adapted to be brought into engagement with the element 53 to rock the latter when the dog 55 is rocked about its support in one direction and in a manner to be hereinafter described and for the purposes to be set forth.

This dog 55 is adapted to be rocked or shifted preferably by means of a foot treadle 58 pivotally supported as at 59 in any convenient position for the operator. The treadle is connected by means of an arm 60 through the medium of ay link 61 with the lever 62 pivotally supported intermediate its ends as at 63, one end of the lever being connected as at 64 with the link 61 and the other end of the lever 62 is connected by means of a link 65 to the dog 55, one end of the link 65 being pivotall connected as at 66 with the lever 62 an at 67 with the dog 55, a spring 68 being anchored at one end as at 69 with the element 53 and by its other end as at 70 with the dog 55 for normally holding the shoulder 57 of the dog out of engagement with the element 53. Thus it will be seen that with the construction thus far described the valves 32-34 may be controlled by the operation of the treadle 58 in the. following manner. When the operator depresses the treadle 59 in the direction indicated by the arrow in Fig. l, it will be seen that the lever 62 will be rocked in a direction to move the shoulder 57 of the dog 55 against the element 53 against the stress of the elastic element 68. A continued movement of the parts in this same direction will cause the element 53 to be rocked about its pivot 54 to draw down upon the rod 45 to shift the lever 39 and through the medium of the link 38 and links 36-37, will rock the valves 32-34 to establish communication between the inlet pipe 29 and the top of the cylinder 13 to admit iiuid into the top of the cylinder on one side of the piston 24, which will cause the piston to descend. At the same time the valve 34 will be so adjusted as to cut off communication between the pipe 29 and the other end of the cylinder and will establish communication between the lower end of the cylinder 13 and the outlet 35 to permit the fluid on the lower end of the piston to be discharged into the atmosphere as the piston descends so as not to retard the descent of the piston.

As the piston thus descends it will lower the drill head 11 and in order that this movement of the piston may be communicated to the drill head there is provided a yoke 71 which is connected with the piston rod 21 above the en'd 16 of the cylinder. Connected to one end of this yoke 71 is a bar or rod 72 which extends below the end of the rod 79 and will This shifting movement. downwardly, of the 1,4c1,3es

cylinder and along one side of one of the uprights of the press frame l0. This bar or rod 72 is connected with the drill head 11 so as `to move the drill head and also so that it is adapted for an inde endent movement with respect to the drili head. To that end there is provided on the drill head 11 spaced guides 73-74 through which the bar or rod 72 loosely passes. These guides 73-74 are spaced for a considerable distance from each other and secured to the rod intermediate the guides and for movement with the rod is a collar 75 which may be adjustably positioned upon the rod in any suitable manner such as by means of fastening devices or screws 476. An elastic element such as a coiled spring 77 encompasses the rod 72 with one end resting against the guide 74 and the other end resting against the end of the collar 75. 'Ihe tension of this elastic element 77 is such that it will normally hold the collar 75 against the guide 73 and when the rod 72 l is lowered by the piston in the manner just 25 above described, the tension of the elastic member is such that under normal conditions it will not yield but will force the head 11 downwardly toward the work. When, however, the movement of the drill head is arrested by reason of the drills coming into contact with the work, and when the piston and rod 72 continue their downward movement, the elastic member 77 will yield and permit the rod 72 to continue in its downward movement independently of the drill head 11.

Carried by the rod 7 2 preferably adjacent the guide 73 is an adjustable collar 78 which is adapted, when the rod 72 moves independently with respect to the drill hcad 11. to engage the end of a rod 79. Connected with this rod 79 are spaced arms 80-81 which stand asti-ide of the controllingr element or lever 12 of the mechanical feeding mechanism of the press and which mechanical mechanism is of the ordina and' well known type usual in machines o this character. The rod 79 may be guided by suitable guides, preferably the guides 73-74 and if desired -an additional guide.82 may be connccted with the rod 79 to stand astride of and move against the adjacent portion of the rod 72. With this construction and as the rod 72 continues in its downward movement independently of the head 11, it will be seen that the collar 78 will engage the shift the latter.

rod 79 will cznse the arm 8O to shift the controlling element 12 and set the mechanical feeding mechanism into operation for operating the drill.

Connected also with the yoke 71 and operating preferably on the other side of the frame 10 is4 a bar or rod 83 which operates through suitable guides and is of a length to terminate adjacent the rocking support 53 and carried by this bar 83 is a collar 84 having a shoulder 85. The collar is adjustably supporte-d by the rod 83 by means of a suitable fastening device 8G whereby the position of the collar may he varied with respect to the rod 83. Arranged within the path of movement of the shoulder 85 of the collar 84 is a pawl 87 which is pivotally supported as at 88 upon the rocking support 53 and a spring 89 may bc provided between the dog 55 and the pawl 87 which tends normally to maintain the end of the pawl 87 within the path of movement of the shoulder 85. Secured also to the bar or rod 83 at any desired distance above the collar 85 is another collar 9() which may be adjustably secured to the bar or rod by means of a suitable fastening device 91. In order to trip the pawl 87 when the dog 55 is rocked about its pivot 54 any suitable connection imay be provided between the two such for instance as an element 92, one end of which is connected with the pawl 87 and `thc other end passes through a suitable guide 93 carried by the end 56 of the dog 55 and the extremity 94 ot' the element 92 is preferably deficcted as shown to prevent the parts from separating. Thus when the dog 55 is rocked about its ivot under the influence of the operation otP the treadle 58fit will be seen that, the end 5G of the dog will pull upon the element 92 and shift the 4pawl 87 against the stress of the sp1-ing 89. At the same time t-he paw] 87 is adapted to move independent] with respect to the dog 55 when the col ars 90--84 are passing the dog on the upward movement of thc rod H3. and this independent movement will be accomplished by reason of the fact that the clement 92 will slide loosely through the guide 93.

It is thought that the operation of this improved structure will be clearly understood from the foregoing, but briefly stated it is as follows:

lVork to be operated on is placed beneath the drill head 11, and assuming the drill head to be in its elevated or uppermost position, with the piston 24 adjacent the top of the cylinder 13, and the jig or pattern by which the. work is to be drilled 1s in position upon the work and below the drills. the operator first actuates the treadle 58 in the direction indicated bv the arrow in Fig. 1. This operation will` through the bar 61. lever 62, and link 65, shift the dog 55 to the left in Fig. 1 and to the right in Fig. 4. The shoulders 57 will engage the rocking support 53 to rock the same about its pivot 54 and this rocking movement of the element- 53 will` through the medium of the link 51, draw down the bar or rod 45 which will rock the lever 39 and shift the valves 32-34 s0 as to establish communication between the inlet pipe 29 through the valve 32, into the top of the cylinder 13. At the same time the links 38-37 will shift the valve 34 to open the bottom of the cylinder on the other side of the piston to the atmosphere. With the parts in this position the fluid will enter the pipe 29 into the 'top of the cylinder to move the piston 24 downwardl As the piston moves downwardly, the drill head 11 will also be given a downward movement toward the work. This downward movenient of the head and piston will continue until the shoulder 85 of the collar 84 strikes the end of the pawl 87 which projects into the path of the downward movement of the shoulder, as shown more clearly in Fi 4. The piston and head will continue a siort distance farther toward the work or sufliciently far to depress the pawl 87 to rock the rocking support 53 about its pivot 54. `his will cause the rod 45 to be shifted upwardly and this upward movement of the rod 45 will rock the arm 39 in the opposite direction and the arm wi l in turn through thc medium of the slot 42 and in 43 connection with the link 38, shift t e latter to rock the valve 32 so as to cut off communication between the pipe 29 and the top of the cylinder 13 and establish communication between the top of the cylinder and the opening 33 which discharges into the atmosphere. This will arrest the movement of the piston and the drill head 11. This arresting movenient can take place Aat any predetermined point in the travel of the head and iston according to the position that the col ar 84 is located upon the rod 72. It is referable to arrest the movement of thev drill head a short distance in advance of the engagement of the drill with the work. This is done so as to permit the operator to adjust the drills with respect to the After the drills have been thus adjusted, the operator then actuates the treadle 58 in thc same direction or in the direction indicated b v the arrow in Fig. 1 to rock the dog 55 and cause its shoulder 57 to engage the rocking support 53 to draw down upon the rod 45 and restablish communication betwccn the inlet pipe 29 of the cylinder to the top of the cylinder to force the piston farther downwardly. This rocking movenient of the dog 55 takes place when the end of thc pawl 87 is under the shoulder 85 of thc collar 84 and it will be seen that as the end 5G of the dog 55 is swung about the pivot 54 the dog will through the medium of the element 92 actuate thepawl 87 about its pivot 88 against the stress of the spring 89 t) move the cnd of the. pawl away from the collar 85 so as to permit the piston, the drill head, and the rod 72 o be further lowered so that the drills will engage the i iillllllli work. The drill head will then continue in its downward movement until the drills engage the work and as the drills do engage the work, the movement of the head 11 will be arrested before the piston in the cylinder travels to the limit of its downward movement. The rod 72 will then be shifted relatively with respect to the drill head throu h the medium of the collar 75 and elastic e ement 77, in the manner set forth. Just as the head 11 is arrested byengagement of the drills with the work, and as the rod 72 continues to move with respect to the head the Ycollar 78 on the rod 72 will encrage the bar 79 to shift the latter downwardly until the arm 80 engages the controlling element or lever 12 to shift the latter at which time the mechanical feeding mechanism of the drill press, will be thrown into operation to effect the drilling.

The actuation of the mechanical feeding mechanism is controlled by shifting the lever 12. On the downward movement of the head, the pressure upon the bar 79, in the manner ljust described causes the arm 80 to rock t le lever 12, about its pivot 12, an this lever, through the medium of the link 12b, will rock the yoke 12e, about its pivot 12, in a direction to cause the yoke to engage and shift the shaft 12, about the pivot 12f. Keyed upon the shaft 12, to rotate therewit but so as to be shifted lon itudinally of the shaft, is a worm 11, t at is adapted to be moved into mesh with a worm i wheel 11", carried by the head 11. r 100 Connected to rotate with the worm wheel 11", is a gear 11, that engages with a rack 11", carried by the upright 10.

Thus when the parts are shifted as above indicated and the worm 11", en ages the 105 worm wheel l1, the head will be ed downwardly by the mechanical feed when motion is imparted to the gear through the shaft 12". The arm 81 serves merely as a support to support the weight of the element 12 when 110 the latter is shifted.

It is during the drilling operation that the collar 90 on the rod 83 will engage the end of the pawl 87 and just at about the completion of the drilling this collar 90 115 will shift the pawl 87 to rock the rocking support 53 to move the rod 45 in the opposite direction from its direction of operation by the treadle or in the same direction that it will be shifted bv the collar 84. This will cut off communication between the inlet pipe 29 and the top of the cylinder and connect the top of the cylinder with the outlet opening 33 to the atmosphere. At the same time that the valve 32 is being 125 shifted to exhaust the top of the cylinder, and thc collar 9U is moving the pawl S7, the valve 34 will be shifted so as to establish communication between the inlet pipe 29 and thebottom of the cylinder 13 to 130 permit the fluid to enter the cylinder under the piston. During this admission of the fluid under the iston, the drill head is still continuing its ownward movement under the influence of the mechanical feed, to the end of the drilling operation, due to the fact that the mechanical feeding mechanism overcomes the air pressure under the piston at that time. This continues until the mechanical drilling controllin element 12 is shifted to render the mec anical feeding inactive. To that end there is provided a suitable stop device 95 mounted u on a suitable support 96 preferabl carried by the frame of the machine an which stop device is arranged in the path of the downward movement of the controlling element to shift the latter while the drill head 11 continues in its movement.

As the lever 12, is thus shifted, it will through the medium of the link 12", rock the yoke 12"', in the opposite direction about its plvot to cause the yoke to move away from the shaft 12, so that the shaft will be caused to rock about the pivot 12', to move the worm 11', out of mesh with the worm wheel 11", the itch or an lar surface of the teeth of t e worm w eel tending to shift the worm and shaft.

If desired and in order to carry the weight of the shifting rod 45 and the parts cooperating therewith, a suitable suspension device 97 such as an expansion sprin may be provided, one end of which may Ee anchored to a suitable fixed support and the other end may be anchored to a collar 98 carried by the rod45.

While the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is 1. In combination with a drill press embodying a traveling drill head, mechanical means for operating the same and means for controlling the said o eratin means; of fluid actuated means or shi ing the said head independently of the first4 said means, means for controlling the operation of the fluid actuated means, and means operating automaticall at two dferent predetermined points 1n the same direction of travel of the said head under the influence of the said fluid actuated means for controlling the latter.

2. In combination with a drill press em-` bodying a traveling drill head, mechanical means for operating the same and means for controlling the said4 o eratin means; of fluid actuated means or shi in the. said head independently of the mechanical means, means for controlling the operation of the fluid actuated means, and means operating automaticall at predetermined points in the same irection of travel of the said head under the influence of the said fluid actuated means for controlling the latter, the said fluid actuating means being also operable to move the drill head in opposite dlrections.

3. In combination with a drill press embodying a traveling drill head, mechanical operating means therefor, and means for controlling the said operatinc| means; of fluid actuated means for shifting said head independently of the said operating means.

means for controlling the operation of the fluid actuated means, and means operating automatically to also control the said fluid actuated means, the said automatically operating means embodying spaced elements adapted to become successively active at different predetermined points in the same direction of travel of the said head.

4. In combination with a drill press embodying a traveling drill head, mechanical operating means therefor, and means for controlling the saidV operating means; of fluid actuated means for shifting said head independently of the first recited means, mechanism for rendering the said fluid actuated means active to move the head in one direction, and means operatively related to the said mechanism and responsive in its operation to the operation of the said head to render the said fluid actuated means inactiveattwo different predetermined points in the same direction of travel of the said head.

5. In combination with a drill press em bodying a travelin drill head mechanical operating means tiierefor, and means for controlling theV said operating means; of fluid actuated means for shifting the head vindependently of the first recited means,

mechanism for rendering the said fluid actuated means active to move the head in one direction, means operatively related to the said mechanism and responsive in its operation to the operation of the said head to render the said fluid actuated means inactive at a predeterminedpoint in the travel of the said head, and means o eratlvely related to the said mechanism, and rendered active by a further movement of the head in the same direction of travel whereby the direction of operation of the said fluid actuated means maybe reversed.

6. In combination with a drill press embodyin a travelin drill head and means for con rolling the ceding movement thereof; of fluid actuated means for also feeding said headL mechanism operable at wlll. to render the said fluid actuated means active, means operating at a predetermined point in the travel of said hea under the Lnuence of the said fluid actuated means for rendering the latter inactive to arrest the feeding movement of the head thereby, and means operating at another predetermined point in the same direction of travel of said head under the influence of the said fluid actu? ated means to render the latter inactive to arrest the feeding movement of the head thereby and to cause the operation of the fluid actuated means to be reversed to retract the head from the work.

7. In combination with a drill press embodying a traveling drill head and means for controlling the feeding movement thereof; of fluid actuated means for also feeding said head, mechanism operable at will to render the said fluid actuated means active, means operating at a predetermined point in the travel of said head under the mflu# ence of the said fluid actuated means for rendering the latter inactive to arrest the feeding movement of the head thereby, and means operating at another predetermined point in the same direction of travel of said head under the influence of the said fluid actuated means to render the latter inactive to arrest the feeding movementof thehead there- `by and to cause the operation of the fluid actuated means to be reversed to retract the head from the work, the said mechanism and the third and fourth recited means embody ing a trip device and spaced elements operating in unison with the said head for successively actuating the said trip device.

8. Mechanism for controlling a drill press head embodying fluid actuated means for moving the head, means for rendering the fluid actuated means active to advance the head to the work, a controlling element separate from the fluid actuated means, means whereby the said Huid actuated means will operate independently of the said head to shift the said controlling element when the movement of the head under the influence of the fluid actuated means is arrested by the work to be o erated upon by the drills, and means whereby the said mechanism will again be set in motion until the completion of the drilling operation.

9. Mechanism for controlling a drill press head embodying fluid actuated means for moving the head, means for rendering the fluid actuated means active to advance the head to the work, a controlling element separate from the fluid actuated means, means whereby the said fluid actuated means will operate independently of the said head to shift the said controlling element 4when the movement of the head under the influence of the fluid actuated means is arrested by the Work to be operated upon by the drills, the third recited means embodying a yield ing connection between; the said head and the said .fluid actuated means, and means whereby said mechanism will 'again be set in motion until the completion of the drilling operation. l

10. Mechanism for controlling a drill press head embodyin fluid actuated means for moving the hea means for rendering the fluid actuated means active to advance the head to the work, a controlling element separate from the said fluid actuated means. means operating automatically to render the fluid actuating means inactive at a predetermined point 1n the movement of the head, means whereby the said fluid actuated means will operate independently of the said head to shift the said controlling element when the movement of the said head under theinfluence of the said fluid actuated means is arrested by the work to be operated upon, and means whereby the mechanism will be again set in motion until the completion of t-he drilling operation.

11. Mechanism for controlling a drill press head embodying fluid actuated means for moving the head, means for rendering the fluid actuated means active to advance the head to the work, a controlling element separate from. the said fluid actuated means, a connection between the said h'ead and the said fluid actuated means, said connection embodying an element for moving the head and adapted for a relative movement with respect thereto, a shoulder on the element, an elastic element disposed between said shoulder and a fixed part of the head whereby the first said element `will advance the head, said elastic element `being adapted to yield to erm'it the first recited element to move in ependently of the head when the latter is arrested by the work to be operated upon, and means whereby the said relative movement of the first recited element with respect to the said head will shift the said controlling element.

12. Mechanism for controlling a drill ,press head embodying fluid actuated means for moving the head, means for rendering the fluid actuated means active to advance the head to the Work, a controlling element separate from the said fluid actuated means` a connection between the said head and the said fluid' actuated means. said connection embodying an element for moving the head and adapted for a relative movement with respect thereto, a shoulder on the element, an elastic element disposed between said shoulder and a fixed part of the head whereby the first said element will advance the head, said elastic element being adapted to yield to permit the first recited element to move independently of the head when the latter is arrested by the work to be o erated upon, means whereby the said relative movement of the first recited element with respect to the said head will shift the said controlling element, and means embodying the second recited means for causing the said fluid actuated means to actuate the said head in the op osite direction.

13. n ,combination with a drill press embodying a traveling drill head, mechanical means for operating the same and means for controlling the sald operating means; of fluid actuated means, means connecting the said fluid actuated means with the head for moving the latter and for also permitting a relative movement of the head and fluid actuated means one with relation to the other` means for controlling the operation of the fluid actuated means, and means operating automatically at two different predetermined points in the same direction of travel of the said head under the influence of the said fluid actuated means for controllin the latter.

14. n combination with a drill press embodying a travelin drill head, mechanical operating means t erefor, and means for controlling the said operating means; of fluid actuated mea'ns for shifting said head independently of the first recited Ameans,`

mechanism for rendering the said fluid actuated means active to move the head in one direction, means operatively connected to the said mechanism and responsive in its operation to the operation of the said head to render the said fluid actuated ineans inactive at two dierent redetermined points in the same direction o? travel of said head, the last recited means embodying a dog, an element pivoted intermediate its ends, said dog being pivoted to the said element at one side of its pivot, a controlling bar con-` nected with the said element on the other side of the pivot and adapted to be shifted when the sald element is rocked by the dog, and means o erable upon the said element for also shifting said bar. l

In testimony whereof I have signed vm name to this s ecication on this 13th day of December, D. 1919.

MARTIN BALCKER. 

